"NGOs are rightly mobilising, but also jostling for position, each claiming that they are doing the most for earthquake survivors," it said.

The Lancet did not name any aid agencies, many of which lost staff members in the disaster, but it questioned the way several have claimed to be "spearheading" relief efforts.

"As we only too clearly see, the situation in Haiti is chaotic, devastating, and anything but co-ordinated," it said.

The editorial argued that the response to the earthquake has highlighted questions about the competitive ethos of large aid agencies. The issue has emerged in past emergencies, including the Asian tsunami in 2004.

"Polluted by the internal power politics and the unsavoury characteristics seen in many big corporations, large aid agencies can be obsessed with raising money through their own appeal efforts. Media coverage as an end in itself is too often an aim of their activities," it said.

Worse still, it accused aid agencies of acting selfishly to the detriment of those they were supposed to be helping. "It seems increasingly obvious that many aid agencies sometimes act according to their own best interests rather than in the interests of individuals whom they claim to help," the Lancet said.

It urged aid agencies to do more to collaborate in response to disasters rather than compete for attention.

"Relief efforts in the field are sometimes competitive with little collaboration between agencies, including smaller, grassroots charities that may have better networks in affected counties and so are well-placed to immediately implement emergency relief," it said.

The editorial said the response to the earthquake should prompt a review of aid agencies and the way they deliver aid.

It said: "Given the ongoing crisis in Haiti, it may seem unpalatable to scrutinise and criticise the motives and activities of humanitarian organisations. But just like any other industry, the aid industry must be examined, not just financially as is current practice, but also in how it operates, from headquarter level to field level."

Since the disaster some countries and aid agencies have criticised the way the US military has led the relief effort. The Lancet editorial was the most sustained criticism to date of the way the aid agencies themselves have reacted.

It concluded: "Although many aid agencies do important work, humanitarianism is no longer the ethos for many organisations within the aid industry. For the people of Haiti and those living in parallel situations of destruction, humanitarianism remains the most crucial motivation and means for intervention."

Andrew Hogg, campaigns editor for Christian Aid, rejected the criticism and detailed the collaboration of the charity with other international NGOs and local groups.

"Within hours of being dug from the rubble in Port-au-Prince last week, Christian Aid's country manager, Prospery Raymond, and programme manager, Abdonnel Dioudou, were liaising with local partner organisations about the provision of relief."

On the charge that aid agencies have been clamouring for attention at the expense of victims, he said: "A journalist working for Christian Aid who was on leave in New York when the quake struck flew immediately to the Dominican Republic and entered Haiti as quickly as she could. Her presence there has been vital in fielding media inquiries about the situation, leaving our assessment team who also flew in, and staff on the ground, free to concentrate on the job of providing humanitarian relief."

Hannah Reichardt, who is emergencies adviser at Save the Children, said: "We have a staff of 200 in Haiti, only two are doing media work. Our response to the crisis in Haiti is a humanitarian one, not a media one."

But she added: "It's absolutely vital that we put effort into media work, because it's the thing that drives our fundraising. It might seem tasteless to some, but it's about giving people the opportunity to donate money to the people of Haiti."

She also pointed out that the work of the Disasters Emergency Committee, an umbrella group of NGOs which has raised £38m for Haiti in the UK, helps to overcome competition between agencies.

"It brings together all of our collective efforts, and it puts the emergency at the forefront not the individual charities."

Brendan Gormley, chief executive of the Disasters Emergency Committee, said the claim that aid agencies had lost their humanitarianism ethos was "risible". The Lancet had failed to "take into account the huge efforts by dedicated staff and volunteers – both Haitians and international experts – who are working tirelessly to bring help to earthquake survivors".

"Co-ordination is improving but remains difficult following large numbers of deaths in both the UN Haiti operation and the Haitian government."

A spokeswoman for Médecins Sans Frontières conceded that the Lancet had some "valid points" but in a statement MSF said: "Tragically we lost a number of our national staff in the earthquake. Our three health facilities were damaged. But the fact that we already had 800 national staff and 30 international experts working in Haiti meant we were able to start helping survivors 25 minutes after the earthquake struck.

"MSF has struggled to put Haiti on the international media agenda for 19 years. It is a scandal that it takes a disaster on this scale for the world to wake up to the plight of the thousands of Haitians who have been living in poverty with limited access to healthcare for many years."